1. Field of the Invention
The present invention relates to a tire interior inspecting method and a tire interior inspecting system using x-rays for inspecting the interior of a tire.
2. Description of the Related Art
When inspecting tires, a sample tire is taken from a tire manufacturing line, the sample tire is set on an x-ray photographing apparatus to form an x-ray image of the interior of the sample tire by using an x-ray film or an image intensifier, and the x-ray image of the interior of the sample tire is examined visually by the operator. A tire conveying line must be stopped every time a tire is sampled, which reduces the productivity of the tire manufacturing line. Therefore, the total inspection of tires is practically impossible and, consequently, tires must be inspected by sampling inspection. A final decision about the quality of the interior of the tire must be made by the operator on the basis of the results of visual inspection of the x-ray image. Decisions based on the results of visual inspection include subjective errors, and the operator's subjective decision is unsuitable for determining rigorous numerical quality assurance references. It is difficult to exclude differences in decision between the operators.
A tire conveyor of the tire conveying line is operated at a very high conveying speed to let a tire pass a fixed position in about 2s. Therefore, the total inspection of tires by the operator is impossible. A special high-speed image processing system is expensive and the development of the special high-speed image processing system involves economical risk.